October 22, 2001
Preparations have begun for inserting the spacecraft
into orbit about the first Lagrangian point, L1, which
will occur on November 16, 2001. The backshell of the
sample return capsule, still in the "cracked open" position,
will be closed completely in preparation for orbit insertion
on November 13. Science will be paused on November 15
and then restarted on November 19.
Recent activities on the spacecraft include continuing
to check out the science instruments and the WIND algorithm,
which will be used to automatically determine the type
of solar wind that is passing by the spacecraft, then
extend or stow the appropriate solar wind collector
arrays to catch particles in the wind.
A solar shock and coronal mass ejection reached the
spacecraft about 16:30 Universal time on October 21.
There was a slight noise increase in the electron monitor
when the shock came through. LANL reports, "Everything
looks hunky-dory."
October 9, 2001
After approximately two days, September 27's solar flare
subsided enough for the spacecraft to return to normal
--the star tracker was no longer plagued with "sparkles"
and the ion and electron monitors were not experiencing
command losses. Since then, nothing out of the ordinary
has happened on the spacecraft.
The sample return capsule's backshell remains in the
"mostly closed" position (10 degrees open). Some "very
fast" solar wind has been seen over the last week. The
science team is trying to reduce the time required for
the sample return capsule to outgas before opening the
canister.
The task force investigating the unexpectedly high
sample return capsule temperatures and its effects continues
to work toward a late October recommendation to the
project concerning the start of science collection.
Correction: The white paint referred to in the
status report is NOT itself degrading, but rather
is thought to have been contaminated by external sources.
This external contamination is believed to have polymerized
under the influence of the sun's ultraviolet emission,
causing a change in the thermal properties of the radiator
to which the paint is applied.
September 27, 2001
The backshell of the sample return capsule has been
left in the "mostly closed" position (10 degrees open)
for the last 10 days. It will most probably stay in
this position for at least another month.
The task force investigating the thermal radiator degradation
continues to solidify their plans to perform battery
and paint-coupon testing and investigate options for
the mission and the spacecraft's systems. The paint
may have bonded with a small amount of contamination
baked on by ultraviolet light. Talks with lithium battery
experts in the industry confirm that the battery will
most likely withstand higher temperatures than the current
limits.
September 17, 2001
On September 15 at about 6:30 a.m. Pacific Daylight
Time, Genesis' sample return capsule backshell was closed
almost all the way, leaving an opening of just about
10 degrees. It will remain in this condition for the
next few weeks in an attempt to correct an overtemperature
condition of the sample return capsule (SRC) battery.
In the process of closing the sample return capsule,
the science monitors were turned off, but they have
now been turned back on and are operating in normal
"wind" mode. The spacecraft is healthy except for the
SRC battery temperature, and is now pointing 6 degrees
off-Sun (normal), precessing at 1 degree/day (normal),
spinning at 1.6 revolutions per minute (normal), with
the SRC battery heater set at 23 degrees celsius (not
normal-bakeout mode), and performing science algorithm
checkout.
August 20, 2001
The Genesis spacecraft is performing well. This
week, the doors of the Genesis Ion Monitor and Genesis
Electron Monitor were successfully opened. After a period
of outgassing, the GEM and GIM were turned on. Their
performance indicates that the door is open. Instrument
checkout was also successfully completed. The science
algorithm WIND, which will ultimately be used to automatically
determine the solar wind regime and deploy or stow the
solar wind collector arrays accordingly, was enabled,
with stellar results. The algorithm correctly determined
a solar wind speed of 380 km/sec, a proton density of
<1/cc, and temperature of 90,000 Kelvin (TK Fahrenheit.)
The spacecraft's measurements were confirmed by comparison
with data from the ACE spacecraft, currently in the
vicinity of Genesis' destination, L1. Daily precession
maneuvers have been successfully implemented to keep
the spacecraft orientation correct with respect to the
Sun. This is important because these precession maneuvers
continue to validate that the spacecraft is in spin-track
mode using star trackers.
August 13, 2001
Genesis has opened its sample return capsule on Friday,
August 17, then opened the covers over the ion and electron
monitors. Earlier in the week, the Genesis flight team
successfully switched the spacecraft from its low gain
antennas to the medium gain antenna, and it is now working
at a rate of 47,400 bits per second. We then turned
on star tracker #1, and initiated the spin track sequence
that uses a combination of the star tracker data and
sun sensor data to determine the spacecraft's orientation.
Spin track is now executing normally.
August 8
After a flawless launch on August 8 at 12:13:40 p.m.
EDT, the Genesis spacecraft is on its mission to "catch
a piece of the sun." At 64 minutes, 12 seconds
into the mission, the Genesis spacecraft separated from
the Delta's third stage. Immediately after separation,
Genesis' solar arrays unfolded and pointed toward the
sun. The spacecraft's signal was successfully acquired
by the NASA Deep Space Network complex at Goldstone,
CA, 85 minutes after launch.
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